Mesoclimas de pastizales de la Sierra de la Ventana

Authors

  • María Julia Kristensen LISEA. Universidad Nacional de La Plata. Diagonal 113 N° 469, (1900) La Plata, Argentina
  • Jorge L. Frangi LISEA. Universidad Nacional de La Plata. Diagonal 113 N° 469, (1900) La Plata, Argentina

Abstract

This study was conducted to recognize local differences in climate, between the main grassland types in the Sierra de la Ventana, Argentina. We compared 6 sites with different elevation, slope and aspect in a W-E attitudinal transect (400-1100 m asl). Simultaneous hourly data were registered during selected representative days of every season. The climatic variables measured were: air temperature, relative humidity, atmospheric saturation deficit pressure, light intensity, wind velocity, air evaporative capacity, and soil temperature. PCA was applied for seasonal and annual comparison of sites. We concluded that the sites showed sufficient climatic differences to recognize 6 mesoclimates. The greatest dissimilarity occurred between lowland and mountain sites. The former were warm, anisothermic and showed higher diurnal evaporative capacity. Steep SW slopes were similar to the lowland sites in summer, but in the other seasons were cold, isothermic, very humid and received low radiation; they seemed more continental. Mountain summits and high ridges showed extreme climatic conditions: they were colder, windy, and had the highest evaporative air capacity, reduced in winter because of the high cloudiness enclosing them. NE and SW gentle slopes showed intermediate conditions between the upper and lower sites; both sites showed differences that were clearly related to aspect. The temperature gradient observed support the existence of an altitudinal bioclimatic unit, a montane belt located above 750 m asl, unique in the province of Buenos Aires.

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Published

1995-06-01

How to Cite

Kristensen, M. J., & Frangi, J. L. (1995). Mesoclimas de pastizales de la Sierra de la Ventana. Ecología Austral, 5(1), 055–064. Retrieved from https://ojs.ecologiaaustral.com.ar/index.php/Ecologia_Austral/article/view/1683

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Section

Articles